CLIMATE CHANGE AND STOMATAL PHYSIOLOGY

Stomata control the uptake of CO2 into the leaf along with water loss through transpiration and are critical for maintaining plant water status and leaf temperature. The predicted changes in future climate conditions; including atmospheric [CO2], temperature, and water availability will greatly influence stomatal development and functional response. As stomata account for 95% of terrestrial gaseous fluxes of water and carbon, their behaviour has major consequences for global hydrological and carbon cycles, with implications for precipitation patterns, land run-off and drought events. Furthermore, as water demand for agricultural practices is predicted to increase, crop production for sustainable food security will require improvements in plantwater use efficiency, to which stomatal conductance and dynamic responses to environmental conditions are key components. Stomatal response is often the combination of several environmental and internal stimuli, and is, therefore, difficult to predict across ecosystem types. Here, we review stomatal response to key environmental factors at the leaf and ecosystem levels, and highlight the influence of changes in stomatal anatomical and functional behaviour on earth systems and ecosystem function in the face of climate change.